Police have found the DNA of a newly-identified suspect on explosives used in last year's deadly Paris attacks, but Belgium's prosecutor has admitted they are "far from solving the puzzle" of the massacre.

Prosecutors identified the new accomplice as 24-year-old Najim Laachraoui, until now known by his false name of Soufiane Kayal.

"The investigation showed that Soufiane Kayal can be identified as Najim Laachraoui, born on May 18, 1991 and who travelled to Syria in February 2013," prosecutors said in a statement.

Prosecutors said Laachraoui's DNA was found at an apartment used by the Paris attackers in Auvelais, near the central Belgian city of Namur, from where the attacks were planned.

He used the same false name at the border between Austria and Hungary on September 9 when he was travelling with Salah Abdeslam and Mohamed Belkaid.

The announcement follows the capture of Abdeslam, who is believed to be the last surviving member of the jihadist team that carried out the attacks.

Belkaid, a 35-year-old Algerian, was shot dead two days earlier in a police raid in the Forest district of Brussels.

The three men had posed as tourists heading to Vienna on holiday and did not raise suspicions when they were stopped by police.

"Laachraoui's DNA was found at the Auvelais home and at a house in Schaarbeek [in Brussels] which were used by the terrorist group," the prosecutors said in the statement.

They appealed to the public to contact police with any information about Laachraoui or his whereabouts.

Investigators suspect that both Laachraoui and Belkaid spoke to some of the jihadists by phone on the evening of the attacks targeting the Bataclan concert venue, restaurants, bars and the Stade de France stadium.

"We have not a bad amount of pieces of the puzzle and in the last few days several pieces have found their place," Belgian prosecutor Frederic Van Leeuw told a news conference in Brussels, flanked by Paris prosecutor Francois Molins.